The sign says "Trucks, Stop Here, Check Brakes, Steep Hill Ahead." Ask almost anyone and they would likely tell you that this sign only applies to heavy commercial trucks equipped with air brakes. This is not the case however, the sign applies to all trucks with a licensed Gross Vehicle Weight (GVW) of more than 5,500 kg. regardless of brake system type. It could include everything from a truck tractor to a pickup pulling an RV.